Co nstant-current dynamo



(No Model.)

'0. N. BLACK.

CONSTANT CURRENT DYNAMO.

No. 593,388. Patented Nov. 9,1897.

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CHARLES N. BLACK, OF NEVV HAVEN, CONNECTICUT.

CONSTANT-CURRENT DYNAWEO.

SPECIFICATION forming part of Letters Patent No. 593,388, dated November 9, 1897.

Application filed February l 1897. Serial No. 621,397. (No model.)

To aZZ whom it may concern:

Be it known that 1, CHARLES N. BLACK, of New Haven, in the county of New Haven and State of Connecticut, have invented a new Improvement in Constant-Current Arc-Dynamos; and I do hereby declare the following, when taken in connection with the accompanying drawing and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and whichsaid drawing constitutes part of this specification, and

represents a diagrammatic view of a two-pole eight-bobbin machine having its internal connections arranged in accordance with my invention.

My invention relates to an improvement in constant-current arc-dynamos, the object being to produce a dynamo having its internal and external circuits arranged so as to distribute the potential in such a manner as to keep it within safe working limits, whereby an increase in lamp capacityis secured without a necessary increase in voltage between any two points in the system. My invention is particularly designed to be used in the construction of large machines.

lVith these ends in View my invention consists in the connection of the terminals of the individual bobbins or sets of bobbins of an open-coil constant-current dynamo to segments of different commutator-rings.

My invention further consists in certain details of arrangement, as will be hereinafter described, and pointed out in the claims.

The accompanying drawing is a diagrammatic representation of the application of my invention to a constant-current open-coil arcdynamo. The armature-core I has bobbins A A, B B, C C,and D D wound upon it. Each of these bobbins is connected to the diametrically opposite bobbin, but is entirely distinct from all of the other bobbins and has no electrical connection with them except through the brushes X X Y Y and through the outside lamp-circuits L and L. The bobbin A is shown as wound upon the outside or top of the bobbin A, the bobbin B upon the outside or top of the bobbin B, the bobbin C upon the bobbin C, and the bobbin D upon the bobbin D, but this is not essential, for, if preierrechthe bobbin A might be located at the side instead of on top of the bobbin A, and so on with the other bobbins. If the bobbins are located side by side, as just suggested, it may be found necessary to ad just the brushes either forward or backward slightly in order to equalize the sparking. Such an adjustment may also be necessary, even when the bobbins are superposed, as shown in the drawing, to compensate, as it were, for inequalities in the construction or in the materialsemployed. The commutatorsegments to which the various bobbins are connected are designated by a a, b b, c c, and d cl. The brushes X and Y and X and Y bear upon these segments. The field-magnets F and F are located in the lamp-circuits L and L, before mentioned. Each of the said lamp-circuits is represented with five lamps in it, these being represented in the conventional way by crosses. Of course the number of lamps may be varied as desired, and it is not necessary that there should be the same number in each circuit. The connections of the bobbins C and C and the bobbins D and D to their proper commutatorsegments 0 c and d d, respectively, are for convenience omitted, but it may be understood that the said connections are identical in arrangement with the connections shown between the bobbins A A and the commutator-segments a a and the connections between the bobbins B B and the commutatorsegments 1) b. The commutator-segments a", b, c, and 61 form one ring of the commutator, while the commutator-segments a, b, c, and d form the other ring of the commutator. The bobbin A is connected through the wire 0 to the commutator-segment of the outer ring and also through the wire 19, the bobbin B, and the wire q to the opposite commutatorsegment I) of the inner commutator ring. The bobbin A is connected by the wire n to the commutator-segment a of the inner ring and also connected by means of the wire on, the bobbin B, and the wire 4' to the commutater-segment o of the outer commutatorring. The bobbin B is connected by the wire q directly to the commutator-segment b of the inner commutator ring and also connected through the wire 10, the bobbin A, and the wire 0 with the commutator-segment a of the outer commutator-ring. The bobbin B is connected by the wire '1" directly to the commutator-segment l) of the outer commutator-ring, and through the wire m the bobbin A, and the wire a to the outer segment ct of the inner colnmutator-ring. The conneetion of the bobbins C and O and D and D are identical in arrangement with the connections just described for the bobbins A and A and B and B, but are omitted so as to avoid the confusion which would result from multiplying the wires.

It will thus be observed that under my improved arrangement the respective bobbins of the machine are connected to opposite segments of different and distinct commutatorrings instead of to opposite segments of the same commutator-ring, ashas been done heretofore. Thus the bobbins A and 13 are electrically connected not to opposite segments of the same commutator-ring, but to opposite segments of different and distinct commutator-rings. The same is true of all the other bobbins. Here I may remark that heretofore in machines of this type each commutator-segment has always had an angular displacement with respect to all oi. the other commutator-segments of the same pair of rings.

By the term angular displacement I mean to describe the arrangement which has heretofore obtained and under which the ends of all of the commutater-segments have been dodged or placed out of alinement.

Under my invention, as will be observed by reference to the drawing, the ends of the complementary commutator-segm cuts are directly opposite an d coincident and intersected by a radial plane emanating from the center of the armatlire-shaft. Thus the commutator-segments a and a of the outer and inner commutator-rmgs, respectively, are complementary and have their ends directly opposite each other and coincident and in position to be intersected by a radial plane emanating from the center of. the armatureshaft.

The machine shown has two rings, but if this number were increased, say, to four rings then the counnmater-segments of the second pair of rings would have an angular displacement with respect to the comn'iutator-segments of the first pair of rings, but the segments of the respective pairs of rings would have no angular displacement with respect to each other, and so on.

I have already pointed out that in my improved machine the complem entary segments of each pair of rings have no angular displacement with respect to each other. I should also point out that in my improved machine the brushes of corresponding sign are also arranged substantially without angular displacement. I say substantially with.- out angular displacement because they may be slightly staggered or deflected with respect to each other in adjusting them either forward or backward to equalize the sparking and compensate for imperfections of construction and inequalities of material; but

the positive brushes X and Y (shown. .in the drawing) have no angular displacementwith respect to each other; no more have the nega tive brushes X and Y.

Having now described the arrangement of the connections in the machine chosen for illustration I will proceed to trace the path of the current. Starting at any point surh, for instance, as the brush X,which is the positive brush the current passes in the direction of the arrow, around the field-magnets F and B, through the lamp-circuit L, to the negative brush K. Here the current divides, a part of it passing to the segment I) and a part to the segment (6, with which the said brush is engaged when the commutator-rings are in the positions in which their segments are shown by the drawing. That portion oi the current entering the comn'nitator-segmen t 1) passes thence through the eonnecting-wire "r to the bobbin I3, through the wire oi. this bobbin and out through the connecting-iiire m to the bobbin A, thence through the wire of this bobbin and. out through the connect ing-wire n, and thence to the commutatorsegment a of the innercoliimutater-ring, from which the current passes to the positive brush Y, in which it joins with the other part oi. the current. That portion of the current ontering the segment at flows through a coin meeting-wire (not shown) to the bobbin I) and around the same, and thence through a connecting-wire (not shown) to the bobbin C, thence through a comiecting-wire (not shown) to the commutator-segineiitc,on which thepositive brushY also bears, The connect ing-wires referred to, but not shown, correspond to the connecting-wires of the bobbins A and 13' and will be understood by reference thereto. From the positive brush Y the current passes through. the lamp-circuit L to the negative brush Y. Here the current again d ivides,a portion of itpassing to the segmeu t7) ot' the inner com inutator-ring and a portion to the segment (Z oi. the same ring. From the COIN- mutator-segmentZ) the current passes through the connecting-wire g to the bobbin 1; and around the same, and out through the con-- necting-wire p,whieh1eads it to the bobbin It, which it passes around, and out into the eonnecting-wirc o, and thence to the cemmutator-segments col the outer cenunutater-ring upon which the positive brush It bears. this point the current joins the other portion of the same current, which divided, as mentioned, at the negative brush Y. The said. other portion of the current flows to the se ment (Z, thence through a coi'uieeting-wiro lution of the armature, but follows a single pathas, for example, when the brushes are hearing only upon the segments 0 and c and d and d.

I have used a two-pole eight-bobbin machine to illustrate my invention, but it is equally applicable to a multipolar machine with a larger number of bobbins. If desired, one of the field-magnets may be included in one lamp-circuit and the other field-magnet in the other lamp-circuit, this principle being applicable in any machine constructed under my invention without regard to size.

I may call attention to the fact that the external connections of my improved machine are like the external connections of machines knownto the art as the old Brush machines.

It is a peculiarity of a machine connected up in accordance with my invention that the lamps and field-circuits are interposed between the segments of the same commutatorring.

I wish it understood from the foregoing modifications suggested and of others that may obviously be made that I do not limit myself to the exact arrangement herein shown and described, but hold myself at liberty to make such changes and alterations as fairly fall within the spirit and scope of my invention.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-- 1. An open-coil, constant-current dynamo, having the terminals of its individual bobbins or sets of connected bobbins connected to segments of different commutator-rings.

2. An open-coil, constant-current dynamo, having the complementary segments of each pair of its commutator-rings arranged without angular displacement with respect to each other, and also having its brushes arranged substantially without angular displacement so far as the brushes bearing upon the complementary segments of any two pairs of commutator-rings are concerned. 7

3. An open-coil, constant-current arc-dynamo, having the terminals of its individual bobbins or sets of connected bobbins connected to opposite segments of different and distinct commutator-rings, the complementary segments of which have no angular displacement with respect to each other.

4. An opencoil, constant-current arc-dynamo, having .two or more generating-bobbins or sets of bobbins, and having its internal connections arranged for the interposition of lamp and field circuits between the brushes bearing upon the segments of the same ring;

5. An open-coil, constant-current arc-dynamo having the terminals of its individual bobbins or sets of connected bobbins connected to opposite segments of different and distinct commutator-rings, and its lamp-circuits connected between brushes bearing on sections of the same ring.

6. A method of connecting two or more lamp-circuits with an open-coil constant-current dynamo, the said method consisting in interposing the several bobbins or sets of bobbins between separate and distinct com- -mutator-rings, and in interposing the lamp and field circuits between brushes bearing on segments of the same ring, whereby increase in lamp capacity is secured without any necessary increase in voltage between any two points in the system.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

CHAS. N. BLACK.

Witnesses:

FRED. C. EARLE, GEORGE D. SEYMOUR. 

